A Neurodynamics Control Strategy for Real-Time Tracking Control of Autonomous Underwater Vehicles

Size: px
Start display at page:

Download "A Neurodynamics Control Strategy for Real-Time Tracking Control of Autonomous Underwater Vehicles"

Transcription

1 THE JOURNAL OF NAVIGATION (4), 67, 3 7. The Royal Institute of Navigation 3 doi:.7/s A Neurodynamics Control Strategy for Real-Time Tracking Control of Autonomous Underwater Vehicles Daqi Zhu, Xun Hua and Bing Sun (Laboratory of Underwater Vehicles and Intelligent Systems, Shanghai Maritime University) ( zdq367@yahoo.com.cn) A biologically inspired neurodynamics-based tracking controller of underactuated Autonomous Underwater Vehicles (AUV) is proposed in this paper. The proposed control strategy includes a velocity controller with biological neurons and an adaptive sliding mode controller. The biological neurons are embedded into the backstepping velocity controller to eliminate the sharp speed jumps commonly existing in vehicles due to tracking errors changing suddenly. The outputs of the velocity controller are used as the command inputs of the sliding mode controller, and the thruster control constraints problems that are commonly seen in the backstepping control of AUV are solved by the proposed controller. Simulation results show that the control strategy achieved success in smoothly tracking AUV position and velocity. KEY WORDS. AUV.. Tracking control. 3. Biologically inspired neurodynamics. 4. Backstepping control. Submitted: 4 March 3. Accepted: 9 July 3. First published online: 9 August 3.. INTRODUCTION. Autonomous Underwater Vehicles (AUVs) are being extensively used by the scientific, oil and gas, and military communities (Liu et al., ; Zheng et al., 3). Real-time tracking control is a fundamentally important issue for AUV systems, achieved by the use of adequate position sensors and generally by the adoption of advanced control approaches. However, how to effectively control an AUV to precisely track the desired vehicle trajectory is still a challenging problem. The existing tracking control methods for AUVs can be classified as follows:.. Proportional-Integral-Derivative (PID) control strategy. PID control strategy (De Paula and Ferreira, ; Antonelli et al., ) is the most commonly used approach for mobile robot tracking control. It is widely used for linear control systems with a single input and single output, but for systems with multiple inputs and multiple outputs, the control effect is not ideal. As the AUV dynamic model is non-linear, both model parameters and ocean disturbances are uncertain and the traditional PID control effect has disadvantages.

2 4 DAQI ZHU, XUN HUA AND BING SUN VOL Backstepping Control Strategy. The backstepping kinematic controller has been widely used in mobile robot tracking control (Yang and Luo, 4; Tsai et al., 4) and it also adapted to AUV use (Jon et al., 8). The main idea of the backstepping algorithm is to define a velocity controller that stabilizes the closed-loop system (Sharma et al., ). It can deal with large initial state errors, but has major disadvantages. Large state errors can cause large control velocity and sharp speed jumps when a sudden tracking error occurs. This means that the required acceleration and forces are very large, and even infinite, may exceed the vehicle s control constraints and is usually impossible to implement practically..3. Neural Network Control Method. The neural network control method (Kodogiannis, 3; Pepijn et al., 5; Bagheri et al., ) is also used widely in controlling dynamic systems. No exact underwater vehicle model is required and an AUV s nonlinearities can be coped with. However, the problem with this approach is that the neural network model requires on-line and off-line learning in order to make the AUV perform properly. This learning procedure is computationally expensive and may not be fit for a real-time situation (Luo and Yang, 8)..4. Sliding Mode Control Method. It is well known that most physical systems have certain non-linear and various uncertainties and complex hydrodynamic forces are also relatively difficult to calculate. Sliding mode control has been proved to be able to tackle system uncertainties and external disturbances robustly. So it is usually used for dynamic tracking control of AUV (Khadija et al., ; Wallace et al., 8; Pan et al., 999). However, one major disadvantage of the sliding mode approach is the high frequency of chattering (Dongkyoung, ; Bagheri and Moghaddam, 9; Santhakumar and Asokan, ). This high frequency chattering can cause high heat losses in the system and premature wear in thrusters. In addition, the chattering may arouse unmodelled high-frequency dynamics, which in turn destroy system performance..5. Fuzzy Control Approaches. The fuzzy control approach (Wai, 7; Ishaque et al.,, ; Miller et al., ) is employed for controlling uncertain or strongly nonlinear systems without knowing the precise system model. The fuzzy control approach does not need on-line or off-line learning and the computation procedure is relatively simple. The major handicap for fuzzy control is in the formulation of the fuzzy rules. The approach needs a complicated learning mechanism or a specific performance decision table designed by trial-and-error based on human knowledge. Its applications still present certain limitations. Each of the tracking control methods for AUV discussed has advantages and disadvantages, so it is difficult to use a single method to deal with all the problems. In this paper, for the problems of speed jumps and the thruster control constraints for AUV tracking control, we present a kinematic/dynamic control system based on a velocity controller with biological neurons and an adaptive sliding mode controller. First, a novel velocity controller based on biological neurons is constructed, the velocity control outputs produced by the velocity controller are used as the control inputs of the adaptive sliding mode controller, which is designed on the vehicle position error and the biological neural dynamics model to guarantee that the position error is asymptotically stable and eliminates the sharp speed jumps when the tracking error changes suddenly. Then an adaptive sliding mode controller is used to generate the control torque, which is designed to drive the AUV and make the linear and angular velocities of the AUV converge to the reference velocities. Our proposal is

3 NO. A NEURODYNAMICS CONTROL STRATEGY FOR AUV 5 Figure. AUV Coordinate systems. chatter-free and robust under dynamic uncertainties and disturbances, because an adaptive algorithm is used in the sliding mode controller (Zhang et al., 9; Antonelli et al., ; Ding and Wang, 9). Simulation studies have verified that the proposed control system is able to realize real-time dynamic tracking of an AUV and has better performance than the traditional backstepping method. The remainder of this paper is organised as follows: In Section, we present the six degree-of-freedom kinematics and dynamics model of an AUV. In Section 3, thruster configuration and force allocation of one type of AUV are introduced, called Autonomous Remote Vehicle (ARV). In Section 4, the kinematic/dynamic hybrid control strategy is given in detail. Then, simulation results are presented in Section 5, which include an AUV tracking a broken line and a helical line trajectory in three dimensional space. A comparison between the novel hybrid control strategy and the conventional backstepping control method is presented in this section. Finally, the work is concluded in Section 6.. KINEMATICS AND DYNAMICS MODELLING OF AUV.. Kinematic Modelling of AUV. It is normal to classify an AUV s coordinate system into a global coordinate system and a local coordinate system. The spatial position and orientation state vector in the global coordinate system can be expressed as η. The spatial linear velocity and angular velocity state vector in the local coordinate system can be expressed as q. The three dimensional AUV coordinate systems are shown in Figure. We consider that all kinematics equality constraints are independent of time. The position state vector η and the velocity state vector q have the following relations: η = J(η)q () where J [ R 6 6 represents the transformation matrix from the local coordinate system to the global coordinate system. It has been discussed in many papers (Dongkyoung, ; Serdar et al., ).

4 6 DAQI ZHU, XUN HUA AND BING SUN VOL Dynamics Modelling of AUV. The three dimensional six degree-of-freedom dynamics equations of AUV can be expressed as follows (Dongkyoung, ; Serdar et al., ): M q + C( q)q + D( q)q + g(η) =τ + w () τ = BT where M [ R 6 6 is the inertia matrix; C [ R 6 6 is the centrifugal terms and Coriolis matrix; D [ R 6 6 is the hydrodynamic damping matrix; g [ R 6 is the vector of gravity and buoyancy; τ [ R 6 is the control forces and torques on the AUV centre; w is the control forces and torques caused by unknown disturbance including unstructured and modelled dynamics in the local coordinate system; B is the matrix of forces configuration; T is the forces produced by thruster. From Equation (), we can obtain dynamics equality in the global coordinate system through coordinate transformation η = J(η)q. f = M η (η) η + C η (q, η) η + D η (q, η) η + g η (η) =J T τ (3) where M η (η)=j T MJ, C η (q, η) =J T [C MJ J]J, D η (q,η)=j T DJ, g η (η)=j T g. 3. THRUSTER CONFIGURATION AND FORCE ALLOCATION OF AUV. In this paper, we use a particular type of AUV model for simulation. It is from the Laboratory of Underwater Vehicles and Intelligent Systems, Shanghai Maritime University, and will be described in detail below. There is no lateral thruster in our AUV, so v= in the velocity state vector. Usually the model is decoupled and controllable in three degrees-of-freedom (surge, heave and yaw). The reduced position state vector η=[xyzψ] T and velocity state vector q=[u w r] T. The dynamics modelling of the AUV can also be simplified as follows (Lapierre and Jouvencel, 8; Edin and Geoff, 4; Zhu et al., ): (m X u ) u + X u u + X uu u u =τ X (4) (m Zẇ)ẇ + Z w w + Z ww w w =τ Z (5) (I Z Nṙ)ṙ + N r r + N rr r r = τ N (6) The AUV has four thrusters; two thrusters are in the horizontal plane and the other two are in vertical plane. Figure shows its structure. A brief sketch of the vehicle s thruster configuration is shown in Figure 3. The dynamic equation of the AUV can be written by Equation (7), based on the thrusters distribution. We can deduce the relationship between the normalized form of torque and the normalized form of thruster forces as follows: τ = τ X τ Z τ N K K = K K KR KR T T T 3 T 4 (7) τ Zm = KT m (8)

5 NO. A NEURODYNAMICS CONTROL STRATEGY FOR AUV 7 Y 4TH 8cm O X cm 3TH TH 3cm TH Figure. Structure of AUV. Figure 3. Thruster configuration. τ X τ Xm τ Z τ = Zm τ N τ Nm τ Zm = KT m (9) τ Nm = KRT m () T T m T T ˉτ X T m T T ˉτ Z = B ˉτ = B T 3 T 3 ˉτ T N m T 4 () T 4 T m where τ are the values of the surge and heave forces and the yaw torque respectively. K is a constant. R is the distance between the two vertical thrusters. τ m =[τ Xm τ Zm τ Nm ] T are maximum values of the surge and heave forces and the yaw torque for the AUV respectively. [T T T 3 T 4 ] T are the forces of the four thrusters individually. T m represents the max force of an individual thruster. ˉτ is the normalized form [ ] T of τ, T = T T T 3 T 4 is the normalized form of T =[T T T 3 T 4 ] T, 4 ˉτ i 4, i = X, Z, N, 4 T i 4, i =,, 3, HYBRID CONTROL STRATEGY FOR AUV. The trajectory tracking problem of an AUV can be described as: Given an AUV dynamical model and a continuous bounded time varying reference trajectory, design a control law that ensures asymptotically exact tracking of the reference trajectory. This paper focuses on the problem of speed jumps and the thruster control constraints for AUV tracking control. A novel control system is presented in Figure 4, which combines a velocity controller with biological neurons and an adaptive sliding mode controller (Dongkyoung, ). 4.. Kinematic Velocity Controller. A backstepping algorithm is employed in the velocity controller to produce the expected velocity. For the AUV model in three dimensional space, the desired position state and velocity state can be described as

6 8 DAQI ZHU, XUN HUA AND BING SUN VOL. 67 x y z d d d d e e e e x y z V V V V x y z u r c c c e e e u r X Z N T T T T u r x y z x y z Figure 4. The novel control system scheme. η d =[x d y d z d ψ d ] T and q d =[u d w d r d ] T, the actual position state and velocity state can be described as η =[xyzψ] T and q =[u w r] T. The position state error in the global coordinate system is defined as e=η η d =[e x e y e z e ψ ] T. The development of tracking control is to let trajectory η follow the reference trajectory η d smoothly and let the e converge to zero. The position state error in the local coordinate system can be expressed as: e =[e e e 3 e 4 ] T = J T e = J T [ e x e y e z e ψ ] T () cos ψ sin ψ sin ψ cos ψ where J = The backstepping algorithm (Zhang et al., 997) isdefined as follows: u = u d + k v (e cos ψ + e sin ψ) ( r = r d + k ψ sin e ) ( 4 + u d e cos ψ d + ψ e sin ψ d + ψ ) w = w d + k z e 3 where k v, k ψ, k z are constant. By analysing the performance of the velocity controller based on the backstepping approach, this controller smooths the sharp speed jumps when tracking errors change suddenly. This means that the required acceleration and forces/torques are very large and may even be infinite, which may exceed the vehicle s control constraint and it is usually practically impossible. However, the biological neural model has characteristics such as stability, bounded activity and smooth response, that may allow it to be used to produce a bounded and smooth auxiliary signal related to tracking errors to improve the real-time velocity commands. Thus we add a biological neuron model to the velocity controller. Hodgkin and Huxley (95) proposed a model for a patch of membrane in a biological neural system using electrical circuit elements. The model then developed and gave rise to many model variations and applications. A biological neuron model was first proposed by Grossberg (988). The shunting equation is described as: C m dv m dt (3) = (E p + V m )g p +(E Na V m )g Na (E k + V m )g k (4)

7 NO. A NEURODYNAMICS CONTROL STRATEGY FOR AUV where C m is the membrane capacitance. The parameters E k, E na and E p are the Nernst potentials for potassium ions, sodium ions, and negative drain current in the membrane, respectively. g k, g Na and g p are the conductance of potassium, sodium and negative pole, respectively. The above parameters can be simplified: C m =, V =E p + V m, A=g p, B=E Na + E p, D=E k E p, S(t) + =g Na, S(t) =g K. Then the shunting equation can be written as follow: V = AV +(B V)S(t) + (D + V)S(t) (5) where V is the neural activity (membrane potential) of the neuron. Parameters A, B and D are the passive decay rate, the upper and lower bounds of the neural activity, respectively. The variables S + and S represent the excitatory and inhibitory input to a neuron, respectively. The shunting dynamic of an individual neuron can be modelled by this equation. The state responses of the models are limited to the finite interval [ D, B] because of the auto gain-regulation of the model. So we can infer the shunting equation to the following form: V i = AV i +(B V i )f (e i ) (D + V i )g(e i ) (6) where i is the neuron index, f(e i ) =max(e i, ), g(e i ) = max( e i, ). It is guaranteed that the neural activity will stay in this interval for any value of the excitatory and inhibitory inputs. The stability and convergence of the shunting model can be rigorously proved by Lyapunov stability theory (Slotine and Li, 99). It is continuous and smooth. We put the biological neuron model into the traditional velocity controller, so that Equation (3) can be written as: u = u d + k v (V cos ψ + V sin ψ) ( r = r d + k ψ sin V ) ( 4 + u d V cos ψ d + ψ V sin ψ d + ψ ) (7) w = w d + k z V 3 where V i (i =,, 3, 4) represent the outputs of the biological neuron model related to the tracking errors e respectively. Because of the smooth and bounded activity of the shunting model, the sharp speed jumps are inhibited effectively. Thus, the outputs of the velocity controller will become smooth even if the tracking errors change suddenly. The performance of the velocity controller is significantly improved. 4.. Dynamic Sliding Mode Controller. Since sliding mode control can offer many properties, such as fast dynamic response, insensitivity to parametric variations and external disturbance rejection, it has been widely used to control nonlinear dynamic systems. It can also be employed to control AUV (Khadija et al., ; Wallace et al., 8). The sliding mode controller generates forces and torques τ =[τ X τ Z τ N ] T in the AUV, which drive the AUV states towards a sliding mode surface, and then switch on that surface. The forces and torques are applied to AUV to produce actual velocity q. So we can easily get the actual states η by Equation (). We choose the sliding mode surface: ( s = d ) ( ) dt + Λ edt = ė + Λe + Λ edt (8) 9

8 DAQI ZHU, XUN HUA AND BING SUN VOL. 67 where e=q c q =[e u e ω e r ] T is the error between the virtual velocity generated by the velocity controller and the actual velocity of the AUV. Furthermore, there is ṡ = ë + Λė + Λ e = ë + Λ( q c q)+λ e (9) where the system is operating on the sliding mode surface, Equation (9) equals zero. ṡ = ë + Λė + Λ e = ë + Λ( q c q)+λ e = () Equation () is simplified as M q + Cq + Dq + g = τ. Put this into Equation (). ë + Λ( q c M )=((τ Cq Dq g)) + Λ e = () Here, the system dynamic term τ is simply divided into two parts: estimated term and unknown term: τ = ˆτ + τ () So the equivalent control law can be concluded as ( τ eq = ˆM q c + ë Λ + Λ ) e + Ĉq + ˆDq + ĝ (3) where ˆM, Ĉ, ˆD, ĝ are estimated terms. Considering the difficulty of computing ë, we introduce a feedback control method of acceleration error ë = kė (4) The conventional sliding mode algorithm is designed as follows: τ = τ eq + k sgn(s) (5) To eliminate the chattering problem caused by the discontinuous term, an adaptive term is added in the control law to replace the switching term in Equation (5). τ ad = τ est + Ks (6) where τ est is an adaptive term that estimates the unknown term τ. The update rate of τ est is as follows: τ est = Γs (7) We then produce a new siding mode controller, called the adaptive sliding mode controller. The total control law can be defined as: τ = τ eq + τ ad = τ eq + τ est + Ks (8) 5. SIMULATION. The trajectory tracking for the AUV is simulated based on the conventional backstepping control method and the novel hybrid control strategy in this section. The reference trajectories are a broken line and a helical line in threedimensional space. A comparison between the simulation results of the two control methods is presented. The aim of the comparison is to illustrate that the novel hybrid control strategy has advantages over the conventional backstepping control method in driving the AUV onto a desired trajectory, and that there is no problem with speed jumps and thruster control constraints for the proposed hybrid control strategy. The hydrodynamic parameters of the AUV are given in Table.

9 NO. A NEURODYNAMICS CONTROL STRATEGY FOR AUV Table. AUV hydrodynamic parameters. Parameter Value Units Brief Description m 8 kg added mass in u m 33 kg added mass in v m 33 kg added moment of inertia in r d 5 kg/m linear drag in u d kg/m linear drag in v d N m s linear drag in r From Figure 4, we can easily obtain position error e=η η d. We then obtain e from Equation (). e is used as the input of the velocity controller, the output is the expected velocity q c =[u c v c r c ] T. We use velocity error e = q q c =[e u e ω e r ] T as the sliding mode controller s input, the output is torques τ =[τ[ X τ Z τ N ] T. Put into ] T Equation (), the result is the normalized form of forces T = T T T 3 T 4. The forces and torques are applied to the AUV to produce actual velocity q=[u v r] T. Thus we can easily get the actual states η=[xyzψ] T by Equation (). 5.. Broken Line Trajectory Tracking. A typical broken line trajectory is studied first. Its equation is a random function. The three dimensional state vector of the AUV can be expressed as η(t)=[x(t) y(t) z(t) ψ(t)] T, and the actual initial state is η() = [6 ] T. Assume the desired state of the AUV is x d (t) = 3 t + 3, y d (t) = 3 t, z d (t) = 3 t, ψ d (t) = π, t, 4 x d (t) = 3 (t )+6, y d (t) =3, z d (t) =3, ψ d (t) = 4 t, x d (t) = 3 (t )+9, y d (t) = 3 (t )+3, z d (t) = 3 (t )+3, ψ d = π t 5 4 The simulation result of trajectory tracking is shown in Figure 5. The blue dotted line represents the traditional backstepping method and red solid line represents the novel hybrid control strategy. From Figure 5 we can see that it takes a short time to catch up the desired trajectory smoothly for the two methods. Figure 6 shows the two methods both produce error jumps at initial time and at random points. However, the velocity responses are obviously different for the different track control methods. For the traditional backstepping method, sharp speed jumps occur when tracking errors change suddenly at initial time and at random points. For example, the virtual surge speed of the traditional backstepping method jumps to more than 5 m/s at initial time, but for the novel hybrid method this is less than m/s in Figure 7. This means that the required acceleration and forces or moments will exceed their control constraint values at the velocity jump points for the traditional backstepping approach, which is practically impossible. For the hybrid control strategy, due to the shunting characteristics of the biological neuron model, the sharp speed jumps are effectively inhibited. Thus, the outputs of the velocity controller will become smoother even if the tracking errors change suddenly. Figure 8 shows normalized thruster forces. For the traditional backstepping approach, the tracking controller outputs do not meet the thruster control constraint ( 4T 4+ ), for instance, the normalized thruster force T of the

10 DAQI ZHU, XUN HUA AND BING SUN VOL. 67 The reference trajectory The traditional backstepping method The novel hybrid control method 6 4 z(m) 6 4 y(m) 4 x(m) 6 8 Figure 5. Broken line trajectory tracking. y error z error x error The traditional backstepping method The novel hybrid control method orientation error time(s) Figure 6. Tracking error. traditional backstepping method jumps to over ten at the tenth second, but for the hybrid method is less than one. This means that thruster forces in the traditional backstepping approach exceed their maximum values, which is practically impossible. Conversely, the hybrid control method does not exhibit this problem. No control value exceeds its maximum; thus the proposed neurodynamics control strategy is more effective. In addition, from Figures 5 to 8, it can be seen that the hybrid control method is chatter-free and robust under dynamic uncertainties and disturbance because the adaptive sliding mode algorithm is used. 5.. Helical Line Trajectory Tracking. A typical helical trajectory is studied first. The three dimensional state vector of the AUV can be expressed as

11 NO. A NEURODYNAMICS CONTROL STRATEGY FOR AUV 3 The traditional backstepping method The novel hybrid control method uc(m/s) rc(m/s) wc(rad/s) time(s) Figure 7. The velocity of the AUV. T T T3 The traditional backstepping method The novel hybrid control method T time(s) Figure 8. The forces of thrusters. η(t)=[x(t) y(t) z(t) ψ(t)] T. Assume the desired state is x d (t) =sin( 5*t), y d (t)= cos ( 5*t), z d (t) = *t, ψ d (t) = 5*t; the actual initial state η() = [x() y() z() ψ()] T =[ 5 5 ] T. The simulation result of trajectory tracking is shown in Figure 9. The blue dotted line represents the traditional backstepping method and the red solid line represents the hybrid control strategy. From Figure 9 we can see that it takes a short time to catch up the desired trajectory smoothly for the two methods. Figure shows the two strategies both produce error jumps at initial time, but the velocity responses are obviously different. From Figure, the virtual velocity based on the traditional backstepping approach gives rise to sharp speed jumps when tracking errors change suddenly. For example, the virtual heave speed jumps to more than 8 m/s at initial time, but for the hybrid method it is less than m/s. This means that the required acceleration and forces or moments will exceed their control constraint values at the velocity jump points for the traditional backstepping approach, which is practically

12 4 DAQI ZHU, XUN HUA AND BING SUN VOL. 67 The reference trajectory The traditional backstepping method The novel hybrid control method 4 3 z(m).5.5 y(m) x(m).5.5 Figure 9. Helical line trajectory tracking. z error x error y error The traditional backstepping method The novel hybrid control method orientation error time(s) Figure. Tracking error. The traditional backstepping method The novel hybrid control method uc(m/s) rc(m/s) wc(rad/s) time(s) Figure. The velocity of the AUV.

13 NO. A NEURODYNAMICS CONTROL STRATEGY FOR AUV T The traditional backstepping method The novel hybrid control method T T T time(s) Figure. The forces of thrusters. impossible. Compared with the traditional backstepping approach, the virtual velocities of the hybrid method are smooth without any sharp jumps. Normalized thruster forces are shown in Figure. For the traditional backstepping approach, the tracking controller outputs do not meet the thruster control constraint ( 4 T 4 +). For instance, the normalized thruster force T 3 of the traditional backstepping method jumps to three at initial time, but the novel hybrid method is less than 5. This means that thruster forces of the traditional backstepping method exceed their maximum values, which is impossible to achieve. For the hybrid control method, no control value exceeds their maximum, and all control values based on the biological neuron model are smaller than the maximum. This proves the efficiency of the proposed hybrid strategy. In addition, from Figures 9 to, it can be seen that the hybrid control method is chatter-free and robust under dynamic uncertainties and disturbances because the adaptive sliding mode algorithm is used in the hybrid controller. 6. CONCLUSIONS. In this paper, a kinematic/dynamics control system based on a velocity controller with biological neurons and an adaptive sliding mode controller is presented for tracking control of an AUV. The biological neuron model can obviously inhibit the sharp speed jumps that commonly exist in the conventional backstepping method. Thus it avoids the required acceleration and forces or moments exceeding their control constraint values at the velocity jump points. Also, we employed an adaptive algorithm to the sliding mode controller; an adaptive term is added into the control law to replace the switching term. Thus the adaptive sliding mode control strategy is chatter-free and robust under dynamic uncertainties and disturbances. The simulation studies have verified that the proposed novel control system is able to realize the dynamic tracking of an AUV and has better performance than the traditional backstepping method.

14 6 DAQI ZHU, XUN HUA AND BING SUN VOL. 67 ACKNOWLEDGEMENT This project is supported by the National Natural Science Foundation of China (57998), Research Fund of Ministry Transport of China ( ) and the Project of Shanghai Municipal Education Commission (3ZZ3). REFERENCES Antonelli, G., Chiaverini, S., Sarkar, N. and West, M. (). Adaptive control of an autonomous underwater vehicle: experimental results on ODIN. IEEE Transactions on Control Systems and Technology, 9, Bagheri, A., Karimi, T. and Amanifard, N. (). Tracking performance control of a cable communicated underwater vehicle using adaptive neural network controllers. Applied Soft Computing,, Bagheri, A. and Moghaddam, J. J. (9). Simulation and tracking control based on neural-network strategy and sliding-mode control for underwater remotely operated vehicle. Neurocomputing, 7, De Paula, C. F. and Ferreira, L. H. C. (). An Improved Analytical PID Controller Design for Non-Monotonic Phase LTI Systems. IEEE Transactions on Control Systems and Technology,, Ding, H. and Wang, D. S. (9). Autonomous Underwater Vehicle Heading Control Based on Sliding Mode Fuzzy Control. Proceedings of the Second International Conference on Modelling and Simulation, Manchester, England, Dongkyoung, C. (). Global Tracking Control of Underactuated Ships With Input and Velocity Constraints Using Dynamic Surface Control Method. IEEE Transactions on Control Systems and Technology, 9, Edin, O. and Geoff, R. (4). Thruster fault diagnosis and accommodation for open-frame underwater vehicles. Control Engineering Practice,, Grossberg, S. (988). Nonlinear neural networks: Principles, mechanisms, and architecture. Neural Networks,, 7 6. Hodgkin, A. L. and Huxley, A. F. (95). A quantitative description of membrane current and its application to conduction and excitation in nerve. The Journal of Physiology, 7, Ishaque, K., Abdullah, S. S., Ayob, S. M. and Salam, Z. (). Single Input Fuzzy Logic Controller for Unmanned Underwater Vehicle. Journal of Intelligent and Robotic Systems, 59, 87. Ishaque, K., Abdullah, S. S., Ayob, S. M. and Salam, Z. (). A simplified approach to design fuzzy logic controller for an underwater vehicle. Ocean Engineering, 38, Jon, E. R., Asgeir, J. S. and Kristin, Y. P. (8). Model-Based Output Feedback Control of Slender-Body Underactuated AUVs: Theory and Experiments. IEEE Transactions on Control Systems Technology, 6, Khadija, D., Majda, L. and Said, N. A. (). Discrete second order sliding mode control for nonlinear multivariable systems. Proceedings of 6th IEEE Mediterranean Electrotechnical Conference (MELECON), Yasmine Hammamet, Kodogiannis, V. (3). Direct adaptive control of underwater vehicles using neural networks. Journal of Vibration and Control, 9, Lapierre, L. and Jouvencel, B. (8). Robust Nonlinear Path-Following Control of an AUV. IEEE Journal of Oceanic Engineering, 33, 89. Liu, F., Cui, W. C. and Li, X. Y. (). China s first deep manned submersible. JIAOLONG, China Earth Science, 53, Luo, C. and Yang, S. X. (8). A bio-inspired neural network for real-time concurrent map building and complete coverage robot navigation in unknown environment. IEEE Transaction on Neural Network, 9, Miller, J., Flowers, G., Bevly, D. (). A System for Tracking an Autonomously Controlled Canine. Journal of Navigation, 65, Pan, M. L., Seok, W. H. and Yong, K. L. (999). Discrete-time quasi-sliding mode control of an autonomous underwater vehicle. IEEE Journal of Oceanic Engineering, 4, Pepijn, W. J., Colinvan, V. F. and Daniel, T. (5). Neural network control of underwater vehicles. Engineering Applications of Artificial Intelligence, 8,

15 NO. A NEURODYNAMICS CONTROL STRATEGY FOR AUV Santhakumar, M. and Asokan, T. (). Investigations on the Hybrid Tracking Control of an Underactuated Autonomous Underwater Robot. Advanced Robotics, 4, Serdar, S., Bradley, J. B. and Ron, P. P. (). Redundancy resolution for underwater mobile manipulators. Ocean Engineering, 37, Sharma, N., Gregory, C. M., Johnson, M. and Dixon, W. E. (). Closed-Loop Neural Network-Based NMES Control for Human Limb Tracking. IEEE Transactions on Control Systems and Technology,, Slotine, J. J. E. and Li, W. (99). Applied nonlinear control. New Jersey: Prentice Hall. Tsai, P. S., Wang, L. S. and Chang, F. R. (4). Systematic backstepping design for b-spline trajectory tracking control of the mobile robot in hierarchical model. IEEE International Conference on Networking, Sensing and Control, Taipei, Taiwan, Wai, R. J. (7). Fuzzy sliding-mode control using adaptive tuning technique. IEEE Transactions on Industrial Electronics, 54, Wallace, M. B., Max, S.D. and Edwin, K. (8). Depth control of remotely operated underwater vehicles using an adaptive fuzzy sliding mode controller. Robotics and Autonomous Systems, 56, Yang, S. X. and Luo, C. (4). A neural network approach to complete coverage path planning, IEEE Transactions on Systems, Man, and Cybernetics, Part B: Cybernetics, 34, Zhang, L. J., Qi, X. and Pang, Y. J. (9). Adaptive output feedback control based on DRFNN for AUV. Ocean Engineering, 36, Zhang, Y.L., Velinsky, S. A. and Feng, X. (997). On the tracking control of differentially steered wheeled mobile robots. Journal of Dynamic Systems, Measurement and Control, 9, Zheng, H., Wang, H.B. and Wu, L. (3). Simulation Research on Gravity-Geomagnetism Combined Aided Underwater Navigation. Journal of Navigation, 66, Zhu, D.Q., Liu, Q. and Hu, Z. (). Fault-tolerant control algorithm of the manned submarine with multi-thruster based on quantum-behaved particle swarm optimization. International Journal of Control, 84,

16 本文献由 学霸图书馆 - 文献云下载 收集自网络, 仅供学习交流使用 学霸图书馆 ( 是一个 整合众多图书馆数据库资源, 提供一站式文献检索和下载服务 的 4 小时在线不限 IP 图书馆 图书馆致力于便利 促进学习与科研, 提供最强文献下载服务 图书馆导航 : 图书馆首页文献云下载图书馆入口外文数据库大全疑难文献辅助工具

- CHAPTER 1. Application of HPLC to the Assay of Enzymatic Activities OVERVIEW

- CHAPTER 1. Application of HPLC to the Assay of Enzymatic Activities OVERVIEW - CHAPTER 1 Application of HPLC to the Assay of Enzymatic Activities OVERVIEW This chapter describes the anatomy of an enzyme assay, focusing on the significance of separation and detection in the assay

More information

Computational Electrodynamics

Computational Electrodynamics Computational Electrodynamics The Finite-Difference Time-Domain Method 1 Allen Taflove Artech House Boston London Contents Preface Chapter 1 Reinventing Electromagnetics 1.1 Background 1.1.1 The Heritage

More information

ISSN: (Print) (Online) Journal homepage:

ISSN: (Print) (Online) Journal homepage: Communications in Algebra ISSN: 0092-7872 (Print) 1532-4125 (Online) Journal homepage: http://www.tandfonline.com/loi/lagb20 n-coherent Rings Sang Bum Lee To cite this article: Sang Bum Lee (2002) n-coherent

More information

Effect of grinding forces on the vibration of grinding machine spindle system

Effect of grinding forces on the vibration of grinding machine spindle system International Journal of Machine Tools & Manufacture 40 (2000) 2003 2030 Effect of grinding forces on the vibration of grinding machine spindle system Mohammed Alfares *, Abdallah Elsharkawy Department

More information

Attribute Reduction on Distributed Incomplete Decision Information System

Attribute Reduction on Distributed Incomplete Decision Information System Attribute Reduction on Distributed Incomplete Decision Information System Jun Hu (B), Kai Wang, and Hong Yu Chongqing Key Laboratory of Computational Intelligence, Chongqing University of Posts and elecommunications,

More information

HIGH electric field strength ( ) may cause corona on nonceramic

HIGH electric field strength ( ) may cause corona on nonceramic 1070 IEEE TRANSACTIONS ON POWER DELIVERY, VOL. 22, NO. 2, APRIL 2007 Practical Cases of Electric Field Distribution Along Dry and Clean Nonceramic Insulators of High-Voltage Power Lines Weiguo Que, Stephen

More information

Study of heat and moisture migration properties in porous building materials

Study of heat and moisture migration properties in porous building materials Applied Thermal Engineering 25(2005) 61 71 www.elsevier.com/locate/apthermeng Study of heat and moisture migration properties in porous building materials Z.Q. Chen *, M.H. Shi Department of Power Engineering,

More information

Published online: 27 Jun 2007.

Published online: 27 Jun 2007. This article was downloaded by: [Northwestern University] On: 04 February 2015, At: 07:24 Publisher: Taylor & Francis Informa Ltd Registered in England and Wales Registered Number: 1072954 Registered office:

More information

Pulse Withstand Capability of Self-healing Metalized Polypropylene Capacitors in Power Applications. An Experimental Investigation

Pulse Withstand Capability of Self-healing Metalized Polypropylene Capacitors in Power Applications. An Experimental Investigation 146 IEEE Transactions on Electrical Insulation Vol. 26 No. 1, February 1991 Pulse Withstand Capability of Self-healing Metalized Polypropylene Capacitors in Power Applications An Experimental Investigation

More information

Innovative neutron shielding materials composed of natural rubber-styrene butadiene rubber

Innovative neutron shielding materials composed of natural rubber-styrene butadiene rubber Home Search Collections Journals About Contact us My IOPscience Innovative neutron shielding materials composed of natural rubber-styrene butadiene rubber blends, boron oxide and iron(iii) oxide This content

More information

Using on Air UAT/ADS-B Signal to Simulate 3D Aviation Weather Information

Using on Air UAT/ADS-B Signal to Simulate 3D Aviation Weather Information Using on Air UAT/ADS-B Signal to Simulate 3D Aviation Weather Information Guan-Jhih Liou Shau-Shiun Jan Department of Aeronautics and Astronautics National Cheng Kung University Tainan 70101, Taiwan tryitagain777@gmail.com

More information

FIELD TESTS ON BORED PILES SUBJECT TO AXIAL AND OBLIQUE PULL By Nabil F. Ismael, 1 Member, ASCE

FIELD TESTS ON BORED PILES SUBJECT TO AXIAL AND OBLIQUE PULL By Nabil F. Ismael, 1 Member, ASCE FIELD TESTS ON BORED PILES SUBJECT TO AXIAL AND OBLIQUE PULL By Nabil F. Ismael, 1 Member, ASCE ABSTRACT: The ultimate oblique pull of bored piles in sand was examined by a field testing program. Tests

More information

University, Shenyang, China b State Key Laboratory of Synthetical Automation for Process

University, Shenyang, China b State Key Laboratory of Synthetical Automation for Process This article was downloaded by: [University of Montana] On: 06 April 2015, At: 21:00 Publisher: Taylor & Francis Informa Ltd Registered in England and Wales Registered Number: 1072954 Registered office:

More information

Particle deposition and layer formation at the crossflow microfiltration

Particle deposition and layer formation at the crossflow microfiltration ELSEVIER Journal of Membrane Science 124 (19971 119-128 journal of MEMBRANE SCIENCE Particle deposition and layer formation at the crossflow microfiltration Justus Altmann *, Siegfried Ripperger Technische

More information

The influence of strong crosswinds on safety of different types of road vehicles

The influence of strong crosswinds on safety of different types of road vehicles https://doi.org/10.1007/s11012-019-00952-1 (0456789().,-volV) ( 04567 89().,-volV) STOCHASTICS AND PROBABILITY IN ENGINEERING MECHANICS The influence of strong crosswinds on safety of different types of

More information

IEEE TRANSACTIONS ON SIGNAL PROCESSING, VOL. 54, NO. 3, MARCH

IEEE TRANSACTIONS ON SIGNAL PROCESSING, VOL. 54, NO. 3, MARCH IEEE TRANSACTIONS ON SIGNAL PROCESSING, VOL 54, NO 3, MARCH 2006 809 An Asymptotically Unbiased Estimator for Bearings-Only and Doppler-Bearing Target Motion Analysis K C Ho, Senior Member, IEEE, and Y

More information

Oscillation Damping of a Distributed Generator Using a Virtual Synchronous Generator

Oscillation Damping of a Distributed Generator Using a Virtual Synchronous Generator 668 IEEE TRANSACTIONS ON POWER DELIVERY, VOL. 29, NO. 2, APRIL 2014 Oscillation Damping of a Distributed Generator Using a Virtual Synchronous Generator Toshinobu Shintai, Yushi Miura, Member, IEEE, and

More information

CENSORED REGRESSION QUANTILES * James L. POWELL

CENSORED REGRESSION QUANTILES * James L. POWELL Journal of Econometrics 32 (1986) 143-155. North-Holland CENSORED REGRESSION QUANTILES * James L. POWELL Massachusettes Institute of Technology. Cambndge, MA 02139, USA Umversity of Wisconsm, Madison,

More information

Multiradar Tracking System Using Radial Velocity Measurements

Multiradar Tracking System Using Radial Velocity Measurements Multiradar Tracking System Using Radial Velocity Measurements A. FARINA S. PARDINI Selenia S.p.A., Italy Abstract Multiradar tracking using both position and radial velocity measurements is discussed.

More information

Seismic behavior of bidirectional bolted connections for CFT columns and H-beams

Seismic behavior of bidirectional bolted connections for CFT columns and H-beams Engineering Structures 29 (2007) 395 407 www.elsevier.com/locate/engstruct Seismic behavior of bidirectional bolted connections for CFT columns and H-beams Lai-Yun Wu a,, Lap-Loi Chung b, Sheng-Fu Tsai

More information

Macro meso freeze thaw damage mechanism of soil rock mixtures with different rock contents

Macro meso freeze thaw damage mechanism of soil rock mixtures with different rock contents International Journal of Pavement Engineering ISSN: 1029-8436 (Print) 1477-268X (Online) Journal homepage: http://www.tandfonline.com/loi/gpav20 Macro meso freeze thaw damage mechanism of soil rock mixtures

More information

The Twisting Tennis Racket

The Twisting Tennis Racket Journal of Dynamics and Differential Equations, Vol. 3, No. 1, 1991 The Twisting Tennis Racket Mark S. Ashbaugh, 1 Carmen C. Chiconc, 1'3 and Richard H. Cushman 2 Received July 19, 1989 This paper describes,

More information

Dense Phase Conveying of Fine Coal at High Total Pressures

Dense Phase Conveying of Fine Coal at High Total Pressures Powder Technology, 62 (199) 243-252 243 Dense Phase Conveying of Fine Coal at High Total Pressures D. GEDART and S. J. NG* University of Bradford, Bradford, BD7 1DP (U.K.) (Received October 19, 1989; in

More information

HYDROGENATION OF HIGHLY UNSATURATED HYDROCARBONS OVER HIGHLY DISPERSED PALLADIUM

HYDROGENATION OF HIGHLY UNSATURATED HYDROCARBONS OVER HIGHLY DISPERSED PALLADIUM Applied Catalyclis, 6 (1983) 41-51 Elsevier Science Publishers B.V., Amsterdam - Printed in The Netherlands 41 HYDROGENATION OF HIGHLY UNSATURATED HYDROCARBONS OVER HIGHLY DISPERSED PALLADIUM CATALYST.

More information

Immobilization of heavy metals in the saturated zone by sorption and in situ bioprecipitation processes

Immobilization of heavy metals in the saturated zone by sorption and in situ bioprecipitation processes Hydrometallurgy 83 (2006) 195 203 www.elsevier.com/locate/hydromet Immobilization of heavy metals in the saturated zone by sorption and in situ bioprecipitation processes S. Van Roy, K. Vanbroekhoven,

More information

Preparation of Colloidal Gold Particles and Conjugation to Protein A, IgG, F(ab ) 2, and Streptavidin

Preparation of Colloidal Gold Particles and Conjugation to Protein A, IgG, F(ab ) 2, and Streptavidin Chapter 8 Preparation of Colloidal Gold Particles and Conjugation to Protein A, IgG, F(ab ) 2, and Streptavidin Sadaki Yokota Abstract Colloidal gold probes, including protein A-, IgG-F(ab ) 2 -, and streptavidin-labeled

More information

Evaluation of shelf life of flavored dehydrated products using accelerated shelf life testing and the WeibuU Hazard sensory analysis

Evaluation of shelf life of flavored dehydrated products using accelerated shelf life testing and the WeibuU Hazard sensory analysis E. T. Contis et al. (Editors) Food Flavors: Formation, Analysis and Packaging Influences 1998 Elsevier Science B.V. All rights reserved 627 Evaluation of shelf life of flavored dehydrated products using

More information

Isostasy Geodesy. Definition. Introduction

Isostasy Geodesy. Definition. Introduction Isostasy Geodesy Lars E. Sjöberg a * and Mohammad Bagherbandi a,b a Division of Geodesy and Satellite Positioning, Royal Institute of Technology, Stockholm, Sweden b Department of Industrial Development,

More information

A FIVE YEARS EXPERIENCE OF PULSE COLUMNS EXTRACTION CYCLES FOR THE REPROCES- SING OF FAST BREEDER REACTOR FUELS AT THE MARCOULE PILOT PLANT (SAP)

A FIVE YEARS EXPERIENCE OF PULSE COLUMNS EXTRACTION CYCLES FOR THE REPROCES- SING OF FAST BREEDER REACTOR FUELS AT THE MARCOULE PILOT PLANT (SAP) FIVE YERS EXPERIENCE OF PULSE COLUMNS EXTRCTION CYCLES FOR THE REPROCES- SING OF FST BREEDER RECTOR FUELS T THE MRCOULE PILOT PLNT (SP) MM. CHRVILLT - FBRE - LE BOUHELLEC - HENRY The reprocessing of Phenix

More information

Cold Regions Science and Technology, 16 ( 1989 ) Elsevier Science Publishers B.V., Amsterdam -- Printed in The Netherlands

Cold Regions Science and Technology, 16 ( 1989 ) Elsevier Science Publishers B.V., Amsterdam -- Printed in The Netherlands Cold Regions Science and Technology, 16 ( 1989 ) 291-33 291 lsevier Science Publishers B.V., Amsterdam -- Printed in The Netherlands PHYSICAL PROCSSS DURING FR-THAW CYCLS IN CLAYY SILTS J.-M. Konrad Department

More information

The nearly periodic fluctuations of blazars in long-term X-ray light curves

The nearly periodic fluctuations of blazars in long-term X-ray light curves Astrophys Space Sci (2017) 362:99 DOI 10.1007/s10509-017-3079-y ORIGINAL ARTICLE The nearly periodic fluctuations of blazars in long-term X-ray light curves Hongtao Wang 1 Chao Yin 1 Fenghua Xiang 1 Received:

More information

Impact of CMOS Technology Scaling on the Atmospheric Neutron Soft Error Rate

Impact of CMOS Technology Scaling on the Atmospheric Neutron Soft Error Rate 2586 IEEE TRANSACTIONS ON NUCLEAR SCIENCE, VOL. 47, NO. 6, DECEMBER 2000 Impact of CMOS Technology Scaling on the Atmospheric Neutron Soft Error Rate Peter Hazucha and Christer Svensson, Member, IEEE Abstract

More information

IEEE TRANSACTIONS ON ENERGY CONVERSION 1. Gang Lv, Zhiming Liu, and Shouguang Sun

IEEE TRANSACTIONS ON ENERGY CONVERSION 1. Gang Lv, Zhiming Liu, and Shouguang Sun IEEE TRANSACTIONS ON ENERGY CONVERSION 1 Analysis of Torques in Single-Side Linear Induction Motor With Transverse Asymmetry for Linear Metro Gang Lv, Zhiming Liu, and Shouguang Sun Abstract Due to the

More information

Tracking Control of a Mobile Robot using a Neural Dynamics based Approach

Tracking Control of a Mobile Robot using a Neural Dynamics based Approach Tracking ontrol of a Mobile Robot using a Neural ynamics based Approach Guangfeng Yuan, Simon X. Yang and Gauri S. Mittal School of Engineering, University of Guelph Guelph, Ontario, NG W, anada Abstract

More information

Double-deformable-mirror adaptive optics system for laser beam cleanup using blind optimization

Double-deformable-mirror adaptive optics system for laser beam cleanup using blind optimization Double-deformable-mirror adaptive optics system for laser beam cleanup using blind optimization Xiang Lei, 1,2,3,* Shuai Wang, 1,2,3 Hu Yan, 1,2,3 Wenjin Liu, 1,2,3 Lizhi Dong, 1,2 Ping Yang, 1,2 and Bing

More information

Calculation of constrained equilibria by Gibbs energy minimization

Calculation of constrained equilibria by Gibbs energy minimization Computer Coupling of Phase Diagrams and Thermochemistry 30 (2006) 18 26 wwwelseviercom/locate/calphad Calculation of constrained equilibria by Gibbs energy minimization Pertti Koukkari, Risto Pajarre VTT

More information

Buoyancy and rotation in small-scale vertical Bridgman growth of cadmium zinc telluride using accelerated crucible rotation

Buoyancy and rotation in small-scale vertical Bridgman growth of cadmium zinc telluride using accelerated crucible rotation Journal of Crystal Growth 233 (2001) 599 608 Buoyancy and rotation in small-scale vertical Bridgman growth of cadmium zinc telluride using accelerated crucible rotation Andrew Yeckel, Jeffrey J. Derby*

More information

A SIMPLE DYNAMIC MODEL FOR THE FORMATION OF DEBRIS CLOUDS. Andrew J. Piekutowski

A SIMPLE DYNAMIC MODEL FOR THE FORMATION OF DEBRIS CLOUDS. Andrew J. Piekutowski Int. J. Imp+a'1 Engn,~ Vol. 10, pp. 453 471. 1990 0734-743X/90 $3])0 + 0.()0 Printed it] Great Britain Pergamon Press pie A SIMPLE DYNAMIC MODEL FOR THE FORMATION OF DEBRIS CLOUDS Andrew J. Piekutowski

More information

Journal of Hydrology, 66 (1983) Elsevier Science Publishers B.V., Amsterdam -- Printed in The Netherlands

Journal of Hydrology, 66 (1983) Elsevier Science Publishers B.V., Amsterdam -- Printed in The Netherlands Journal of Hydrology, 66 (1983) 169--182 169 Elsevier Science Publishers B.V., Amsterdam -- Printed in The Netherlands [1] THE USE OF CORRELATION LINKAGES IN THE ASSESSMENT OF DAILY RAINFALL PATTERNS G.N.

More information

Methanol±steam reforming on Cu/ZnO/Al 2 O 3. Part 1: the reaction network

Methanol±steam reforming on Cu/ZnO/Al 2 O 3. Part 1: the reaction network Applied Catalysis A: General 179 (1999) 21±29 Methanol±steam reforming on Cu/ZnO/Al 2 O 3. Part 1: the reaction network Brant A. Peppley *, John C. Amphlett, Lyn M. Kearns, Ronald F. Mann Department of

More information

('I-I)" would yield a noise many orders of magnitude. Electrical conduction and current noise mechanism in discontinuous metal films. H.

('I-I) would yield a noise many orders of magnitude. Electrical conduction and current noise mechanism in discontinuous metal films. H. PH YSCAL REVK% 8 VOLUME 17, N UMBER 6 15 MARCH 197S Electrical conduction and current noise mechanism in discontinuous metal films. H. Experimental M. Celasco, ~ A. Masoero, P. Mazzetti, f and A. Stepanescu

More information

Yo Shimizu a, Akio Ikegami a, Masatomo Nojima a & Shigekazu Kusabayashi a a Department of Applied Chemistry, Faculty of

Yo Shimizu a, Akio Ikegami a, Masatomo Nojima a & Shigekazu Kusabayashi a a Department of Applied Chemistry, Faculty of This article was downloaded by: [Duke University Libraries] On: 06 October 2014, At: 12:23 Publisher: Taylor & Francis Informa Ltd Registered in England and Wales Registered Number: 1072954 Registered

More information

Structure and Thermal Expansion of LiGe, (PO,),

Structure and Thermal Expansion of LiGe, (PO,), JOURNAL OF SOLID STATE CHEMISTRY 9, 18.5-193 (1991) Structure and Thermal Expansion of LiGe, (PO,), M. ALAMI AND R. BROCHU Dkpartement de Chimie de la FucultP des Sciences de I UniversitP Mohamed V, Avenue

More information

Hybridization of accelerated gradient descent method

Hybridization of accelerated gradient descent method https://doi.org/10.1007/s11075-017-0460-4 ORIGINAL PAPER Hybridization of accelerated gradient descent method Milena Petrović 1 Vladimir Rakočević 2,3 Nataša Kontrec 1 Stefan Panić 1 Dejan Ilić 3 Received:

More information

Proceedings of the ASME th International Conference on Ocean, Offshore and Arctic Engineering OMAE2017 June 25-30, 2017, Trondheim, Norway

Proceedings of the ASME th International Conference on Ocean, Offshore and Arctic Engineering OMAE2017 June 25-30, 2017, Trondheim, Norway Proceedings of the ASME 2017 36th International Conference on Ocean, Offshore and Arctic Engineering OMAE2017 June 25-30, 2017, Trondheim, Norway OMAE2017-61230 TEMPERATURE DEPENDENT TORQUE AND DRAG FOR

More information

Desalination 286 (2012) Contents lists available at SciVerse ScienceDirect. Desalination. journal homepage:

Desalination 286 (2012) Contents lists available at SciVerse ScienceDirect. Desalination. journal homepage: Desalination 286 (12) 389 393 Contents lists available at SciVerse ScienceDirect Desalination journal homepage: www.elsevier.com/locate/desal Simultaneous extraction and purification of aloe polysaccharides

More information

A Microprocessor-Based Novel Instrument for Temperature and Thermal Conductivity Measurements

A Microprocessor-Based Novel Instrument for Temperature and Thermal Conductivity Measurements TECHNICAL ARTICLE A Microprocessor-Based Novel Instrument for Temperature and Thermal Conductivity Measurements M. Rehman 1, M. Abdul Mujeebu 2, T.B. Kheng 1, and B.A.J.A. Abu Izneid 1 1 School of Electrical

More information

Mohammad Mahdi Labani Reza Rezaee. obviously with a low organic matter content thermal maturity has no prominent effect on the brittleness as well.

Mohammad Mahdi Labani Reza Rezaee. obviously with a low organic matter content thermal maturity has no prominent effect on the brittleness as well. Rock Mech Rock Eng () 48:149 17 DOI.07/s0060-014-0617-6 ORIGINAL PAPER The Importance of Geochemical Parameters and Shale Composition on Rock Mechanical Properties of Gas Shale Reservoirs: a Case Study

More information

Spatio-Temporal Variability of Seasonality of Rainfall over India. Corresponding Address

Spatio-Temporal Variability of Seasonality of Rainfall over India. Corresponding Address Spatio-Temporal Variability of Seasonality of Rainfall over India Sandeep Sahany 1, Saroj K. Mishra 1, Raju Pathak 1, and Balaji Rajagopalan 2,3 1 Centre for Atmospheric Sciences, Indian Institute of Technology

More information

A Sliding Mode Control based on Nonlinear Disturbance Observer for the Mobile Manipulator

A Sliding Mode Control based on Nonlinear Disturbance Observer for the Mobile Manipulator International Core Journal of Engineering Vol.3 No.6 7 ISSN: 44-895 A Sliding Mode Control based on Nonlinear Disturbance Observer for the Mobile Manipulator Yanna Si Information Engineering College Henan

More information

Lateral Flow Colloidal Gold-Based Immunoassay for Pesticide

Lateral Flow Colloidal Gold-Based Immunoassay for Pesticide Chapter 15 Lateral Flow Colloidal Gold-Based Immunoassay for Pesticide Shuo Wang, Can Zhang, and Yan Zhang Summary In recent years, immunochromatographic lateral flow test strips are used as a popular

More information

Determination of the isotopic ratios of silicon in rocks*

Determination of the isotopic ratios of silicon in rocks* Qeochimica et Cosmochimica Acta, 1954, vol. 5. pp. 40 to 48. Pergamon Prew Ltd., London Determination of the isotopic ratios of silicon in rocks* R. J. ALLENBY** Geophysics Laboratory, Department of Physics,

More information

Effects of cyclic freezing and thawing on mechanical properties of Qinghai Tibet clay

Effects of cyclic freezing and thawing on mechanical properties of Qinghai Tibet clay Cold Regions Science and Technology 48 (2007) 34 43 www.elsevier.com/locate/coldregions Effects of cyclic freezing and thawing on mechanical properties of Qinghai Tibet clay Da-yan Wang, Wei Ma, Yong-hong

More information

Model Reference Adaptive Control of Underwater Robotic Vehicle in Plane Motion

Model Reference Adaptive Control of Underwater Robotic Vehicle in Plane Motion Proceedings of the 11th WSEAS International Conference on SSTEMS Agios ikolaos Crete Island Greece July 23-25 27 38 Model Reference Adaptive Control of Underwater Robotic Vehicle in Plane Motion j.garus@amw.gdynia.pl

More information

A novel bi level optimization model for load supply capability issue in active distribution network

A novel bi level optimization model for load supply capability issue in active distribution network Received: 4 November 2016 Revised: 7 October 2017 Accepted: 11 October 2017 DOI: 10.1002/etep.2492 RESEARCH ARTICLE A novel bi level optimization model for load supply capability issue in active distribution

More information

OPTICAL METHODS OF TEMPERATURE DETERMINATION

OPTICAL METHODS OF TEMPERATURE DETERMINATION Chapter V OPTICAL METHODS OF TEMPERATURE DETERMINATION 1. General Principles The thermal radiation of heated bodies is widely used to study the properties and temperature of radiating substances. If a

More information

Accepted Manuscript. Vibro-acoustic response and sound transmission loss characteristics of truss core sandwich panel filled with foam

Accepted Manuscript. Vibro-acoustic response and sound transmission loss characteristics of truss core sandwich panel filled with foam Accepted Manuscript Vibro-acoustic response and sound transmission loss characteristics of truss core sandwich panel filled with foam M.P. Arunkumar, Jeyaraj Pitchaimani, K.V. Gangadharan, M.C. Leninbabu

More information

TEPZZ Z5 877A_T EP A1 (19) (11) EP A1. (12) EUROPEAN PATENT APPLICATION published in accordance with Art.

TEPZZ Z5 877A_T EP A1 (19) (11) EP A1. (12) EUROPEAN PATENT APPLICATION published in accordance with Art. (19) TEPZZ Z 877A_T (11) EP 3 03 877 A1 (12) EUROPEAN PATENT APPLICATION published in accordance with Art. 3(4) EPC (43) Date of publication:.08.16 Bulletin 16/32 (21) Application number: 14847473.7 (22)

More information

Optimum design and sequential treatment allocation in an experiment in deep brain stimulation with sets of treatment combinations

Optimum design and sequential treatment allocation in an experiment in deep brain stimulation with sets of treatment combinations Received: 30 January 2017 Revised: 8 August 2017 Accepted: 23 August 2017 DOI: 10.1002/sim.7493 RESEARCH ARTICLE Optimum design and sequential treatment allocation in an experiment in deep brain stimulation

More information

Simple Frictional Analysis of Helical Buckling of Tubing

Simple Frictional Analysis of Helical Buckling of Tubing Simple Frictional Analysis of Helical Buckling of Tubing R.F. Mitchell, SE, Enertech Engineering & Research Summary. revious analyses of helical buckling of tubing have not considered frictional forces.

More information

Design and Application of Quadratic Correlation Filters for Target Detection

Design and Application of Quadratic Correlation Filters for Target Detection I. INTRODUCTION Design and Application of Quadratic Correlation Filters for Target Detection ABHIJIT MAHALANOBIS ROBERT R. MUISE S. ROBERT STANFILL Lockheed Martin ALAN VAN NEVEL Naval Air Warfare Center

More information

Effect of Freeze-Thaw Cycles on Triaxial Strength Properties of Fiber-Reinforced Clayey Soil

Effect of Freeze-Thaw Cycles on Triaxial Strength Properties of Fiber-Reinforced Clayey Soil KSCE Journal of Civil Engineering (2017) 21(6):2128-2140 Copyright c2017 Korean Society of Civil Engineers DOI 10.1007/s12205-017-0960-8 TECHNICAL NOTE Geotechnical Engineering pissn 1226-7988, eissn 1976-3808

More information

Effect Of Roller Profile On Cylindrical Roller Bearing Life Prediction Part I: Comparison of Bearing Life Theories

Effect Of Roller Profile On Cylindrical Roller Bearing Life Prediction Part I: Comparison of Bearing Life Theories Tribology Transactions ISSN: 1040-2004 (Print) 1547-397X (Online) Journal homepage: http://www.tandfonline.com/loi/utrb20 Effect Of Roller Profile On Cylindrical Roller Bearing Life Prediction Part I:

More information

A new data reduction scheme for mode I wood fracture characterization using the double cantilever beam test

A new data reduction scheme for mode I wood fracture characterization using the double cantilever beam test Available online at www.sciencedirect.com Engineering Fracture Mechanics 75 (2008) 3852 3865 www.elsevier.com/locate/engfracmech A new data reduction scheme for mode I wood fracture characterization using

More information

VERNIER permanent magnet motors (VPMM) are essentially

VERNIER permanent magnet motors (VPMM) are essentially 2088 IEEE TRANSACTIONS ON INDUSTRY APPLICATIONS, VOL. 53, NO. 3, MAY/JUNE 2017 Torque Performance Comparison Between a Ferrite Magnet Vernier Motor and an Industrial Interior Permanent Magnet Machine Zhentao

More information

APPLICATIONS OF DIGITAL SIMULATION OF GAUSSIAN RANDOM PROCESSES MASANOBU SHINOZUKA 1. INTRODUCTION. Columbia University New York, N.Y., U. S. A.

APPLICATIONS OF DIGITAL SIMULATION OF GAUSSIAN RANDOM PROCESSES MASANOBU SHINOZUKA 1. INTRODUCTION. Columbia University New York, N.Y., U. S. A. APPLICATIONS OF DIGITAL SIMULATION OF GAUSSIAN RANDOM PROCESSES MASANOBU SHINOZUKA Columbia University New York, N.Y., U. S. A. 1. INTRODUCTION In the last two decades, much research effort has been devoted

More information

Catalysis Communications

Catalysis Communications Catalysis Communications 13 (2011) 63 68 Contents lists available at ScienceDirect Catalysis Communications journal homepage: www.elsevier.com/locate/catcom Short Communication Novel BiOI/BiOBr heterojunction

More information

Catalytic Oxidation of Alcohol to Carboxylic Acid with a Hydrophobic Cobalt Catalyst in Hydrocarbon Solvent

Catalytic Oxidation of Alcohol to Carboxylic Acid with a Hydrophobic Cobalt Catalyst in Hydrocarbon Solvent DOI: 10.1002/asia.201700717 Full Paper Alcohol Oxidation Catalytic Oxidation of Alcohol to Carboxylic Acid with a Hydrophobic Cobalt Catalyst in Hydrocarbon Solvent Song Shi, [a] Meng Liu, [a, b] Li Zhao,

More information

Practical and Chemoselective Reduction of Acyl Chloride to Alcohol by Borohydride in Aqueous Dichloromethane

Practical and Chemoselective Reduction of Acyl Chloride to Alcohol by Borohydride in Aqueous Dichloromethane Synthetic Communications ISSN: 0039-7911 (Print) 1532-2432 (Online) Journal homepage: http://www.tandfonline.com/loi/lsyc20 Practical and Chemoselective Reduction of Acyl Chloride to Alcohol by Borohydride

More information

Zhi-bin Zhang Zhi-wei Zhou Xiao-hong Cao Yun-hai Liu Guo-xuan Xiong Ping Liang

Zhi-bin Zhang Zhi-wei Zhou Xiao-hong Cao Yun-hai Liu Guo-xuan Xiong Ping Liang J Radioanal Nucl Chem (2014) 299:1479 1487 DOI 10.1007/s10967-013-2830-2 Removal of uranium(vi) from aqueous solutions by new phosphorus-containing carbon spheres synthesized via one-step hydrothermal

More information

A NUMERICAL MODEL OF CREVICE CORROSION FOR PASSIVE AND ACTIVE METALS

A NUMERICAL MODEL OF CREVICE CORROSION FOR PASSIVE AND ACTIVE METALS Pergamon Corrosion Science, Vol. 38, No. 1, pp. I-18, 1996 Elsevier Science Ltd Printed in Great Britain 0010-938X/96 $15.00+0.00 0010-938X(96)00107-7 A NUMERICAL MODEL OF CREVICE CORROSION FOR PASSIVE

More information

The influence of macrophytes on sedimentation and nutrient retention in the lower River Spree (Germany)

The influence of macrophytes on sedimentation and nutrient retention in the lower River Spree (Germany) Water Research 37 (2003) 569 578 The influence of macrophytes on sedimentation and nutrient retention in the lower River Spree (Germany) Marcus Schulz*, Hans-Peter Kozerski, Thomas Pluntke, Karina Rinke

More information

MODERN spacecraft [1], [2], offshore platforms [3], and

MODERN spacecraft [1], [2], offshore platforms [3], and IEEE SENSORS JOURNAL, VOL. 18, NO. 5, MARCH 1, 2018 2031 Robust Optimal Sensor Placement for Uncertain Structures With Interval Parameters Chen Yang, Zixing Lu, and Zhenyu Yang Abstract This paper proposes

More information

Temperature programmed desorption-ftir investigation of C 1 C 5 primary alcohols adsorbed on -alumina

Temperature programmed desorption-ftir investigation of C 1 C 5 primary alcohols adsorbed on -alumina Applied Catalysis A: General 257 (2004) 225 233 Temperature programmed desorption-ftir investigation of C 1 C 5 primary alcohols adsorbed on -alumina P.A. Clayborne, T.C. Nelson, T.C. DeVore Department

More information

Arctic High-Resolution Elevation Models: Accuracy in Sloped and Vegetated Terrain

Arctic High-Resolution Elevation Models: Accuracy in Sloped and Vegetated Terrain Technical Note Arctic High-Resolution Elevation Models: Accuracy in Sloped and Vegetated Terrain Craig Glennie, Ph.D., P.Eng. 1 Abstract: New high-resolution elevation models for Alaska have recently been

More information

Correlated K-Distributed Clutter Generation for Radar Detection and Track

Correlated K-Distributed Clutter Generation for Radar Detection and Track I. INTRODUCTION Correlated K-Distributed Clutter Generation for Radar Detection Track L. JAMES MARIER, Jr., Member, IEEE United Defense, LP Minneapolis, Minnesota The generation of correlated vectors for

More information

A comparative study of LaBr 3 (Ce 3+ ) and CeBr 3 based gamma-ray spectrometers for planetary remote sensing applications

A comparative study of LaBr 3 (Ce 3+ ) and CeBr 3 based gamma-ray spectrometers for planetary remote sensing applications A comparative study of LaBr 3 (Ce 3+ ) and CeBr 3 based gamma-ray spectrometers for planetary remote sensing applications A. Kozyrev,, I. Mitrofanov, A. Owens, F. Quarati, J. Benkhoff, B. Bakhtin, F. Fedosov,

More information

Journal of Power Sources

Journal of Power Sources Journal of Power Sources 185 (2008) 973 984 Contents lists available at ScienceDirect Journal of Power Sources journal homepage: www.elsevier.com/locate/jpowsour Analysis and control of a hybrid fuel delivery

More information

Effect of Rapid Thermal Cooling on Mechanical Rock Properties

Effect of Rapid Thermal Cooling on Mechanical Rock Properties Rock Mech Rock Eng DOI 10.1007/s00603-013-0523-3 ORIGINAL PAPER Effect of Rapid Thermal Cooling on Mechanical Rock Properties Kwangmin Kim John Kemeny Mark Nickerson Received: 10 October 2012 / Accepted:

More information

KD = diag(lo,2)[n m shad].

KD = diag(lo,2)[n m shad]. IEEE TRANSACTIONS ON ROBOTICS AND AUTOMATION, VOL. 9, NO. 4, AUGUST 1993 461 The arm was initially placed in the vertical equilibrium configuration 8 = (-90 O)T[deg] 6 = (0 0 0 O)T[m]. The desired joint

More information

Observations and modeling of lightning leaders

Observations and modeling of lightning leaders C. R. Physique 3 (2002) 1375 1392 Physique appliquée/applied physics MÉCANISMES PHYSIQUES DU NUAGE D ORAGE ET DE L ÉCLAIR THE PHYSICS OF THUNDERCLOUD AND LIGHTNING DISCHARGE Observations and modeling of

More information

Surface modification of nanofiltration membrane for reduction of membrane fouling

Surface modification of nanofiltration membrane for reduction of membrane fouling This article was downloaded by: [University of South Florida] On: 10 June 2013, At: 01:33 Publisher: Taylor & Francis Informa Ltd Registered in England and Wales Registered Number: 1072954 Registered office:

More information

Journal of Analytical and Applied Pyrolysis 43 (1997) 125%13X. G. de la Puente, J.J. Pis b-*, J.A. Menhdez b, P. Grange a

Journal of Analytical and Applied Pyrolysis 43 (1997) 125%13X. G. de la Puente, J.J. Pis b-*, J.A. Menhdez b, P. Grange a ELSEVIER Journal of Analytical and Applied Pyrolysis 43 (1997) 125%13X JOURNAL OI ANALYTICAL and APPLIED PYROLYSIS Thermal stability of oxygenated carbons functions in activated G. de la Puente, J.J. Pis

More information

Real-time Motion Control of a Nonholonomic Mobile Robot with Unknown Dynamics

Real-time Motion Control of a Nonholonomic Mobile Robot with Unknown Dynamics Real-time Motion Control of a Nonholonomic Mobile Robot with Unknown Dynamics TIEMIN HU and SIMON X. YANG ARIS (Advanced Robotics & Intelligent Systems) Lab School of Engineering, University of Guelph

More information

Autonomous Strapdown Stellar-Inertial Navigation Systems: Design Principles, Operating Modes and Operational Experience

Autonomous Strapdown Stellar-Inertial Navigation Systems: Design Principles, Operating Modes and Operational Experience ISSN 275-187, Gyroscopy and Navigation, 213, Vol. 4, No. 4, pp. 24 215. Pleiades Publishing, Ltd., 213. Published in Russian in Giroskopiya i Navigatsiya, 213, No. 3, pp. 91 11. Autonomous Strapdown Stellar-Inertial

More information

Three-Dimensional Geodesy for Terrestrial Network Adjustment

Three-Dimensional Geodesy for Terrestrial Network Adjustment VOL. 77, NO. $ 3OURNAI, OF GEOPHYSICAL RESEARCH FEBRUARY 10, 1972 Three-Dimensional Geodesy for Terrestrial Network Adjustment D. M. J. Battelle Columbus Laboratories 505 King Avenue, Columbus, Ohio 43201

More information

Separation of phenolic aldehydes, ketones and acids from lignin degradation by capillary zone electrophoresis

Separation of phenolic aldehydes, ketones and acids from lignin degradation by capillary zone electrophoresis JOURNAL OF CHROMATOGRAPHY A ELSEVIER Journal of Chromatography A, 755 (1996) 89-97 Separation of phenolic aldehydes, ketones and acids from lignin degradation by capillary zone electrophoresis Ousmane

More information

TYPE-II phased locked loops (PLLs) incorporating charge

TYPE-II phased locked loops (PLLs) incorporating charge IEEE TRANSACTIONS ON CIRCUITS AND SYSTES I: REGULAR PAPERS 1 On the Stability of Charge-Pump Phase-Locked Loops Aliakbar Homayoun, ember, IEEE, and Behzad Razavi, Fellow, IEEE Abstract This paper employs

More information

arxiv:cond-mat/ v1 [cond-mat.stat-mech] 5 Jun 2002

arxiv:cond-mat/ v1 [cond-mat.stat-mech] 5 Jun 2002 arxiv:cond-mat/0206047v1 [cond-mat.stat-mech] 5 Jun 2002 Endogeneous Versus Exogeneous Shocks in Systems with Memory D. Sornette 1,2 and A. Helmstetter 3 1 Institute of Geophysics and Planetary Physics

More information

Changes in the morphology of organoclays with HDTMA + surfactant loading

Changes in the morphology of organoclays with HDTMA + surfactant loading Applied Clay Science 31 (2006) 262 271 www.elsevier.com/locate/clay Changes in the morphology of organoclays with HDTMA + surfactant loading Hongping He a,b, Ray L. Frost b,, Thor Bostrom b, Peng Yuan

More information

Quantum Yield of a Photochemical Reaction

Quantum Yield of a Photochemical Reaction CHAPTER 4 PHOTOCHEMISTRY Quantum Yield of a Photochemical Reaction Roy H. POTTIER and David A. RUSSELL The Royal Military College of Canada Canada INTRODUCTION Photochemistry - The Foundation of Photobiology

More information

Structure of surface cracks in soil and muds

Structure of surface cracks in soil and muds Ž. Geoderma 93 1999 101 124 Structure of surface cracks in soil and muds B. Velde ) Laboratoire de Geologie, URA 1316 Ecole Normale Superieure, 24 rue Lhomond, 75231 Paris, France Received 9 April 1998;

More information

Supramolecular Cocrystals of Gliclazide: Synthesis, Characterization and Evaluation

Supramolecular Cocrystals of Gliclazide: Synthesis, Characterization and Evaluation Pharm Res (2017) 34:552 563 DOI 10.1007/s11095-016-2075-1 RESEARCH PAPER Supramolecular Cocrystals of Gliclazide: Synthesis, Characterization and Evaluation Renu Chadha 1 & Dimpy Rani 1 & Parnika Goyal

More information

Reasons for the Deactivation of Vanadia Titania Catalysts for Partial Durene Oxidation during Prolonged Performance

Reasons for the Deactivation of Vanadia Titania Catalysts for Partial Durene Oxidation during Prolonged Performance Kinetics and Catalysis, Vol. 4, No. 3, 00, pp. 9 300. Translated from Kinetika i Kataliz, Vol. 4, No. 3, 00, pp. 35 335. Original Russian Text Copyright 00 by Kutepov, Bal zhinimaev. IV RUSSIAN CONFERENCE

More information

Adaptive Robust Tracking Control of Robot Manipulators in the Task-space under Uncertainties

Adaptive Robust Tracking Control of Robot Manipulators in the Task-space under Uncertainties Australian Journal of Basic and Applied Sciences, 3(1): 308-322, 2009 ISSN 1991-8178 Adaptive Robust Tracking Control of Robot Manipulators in the Task-space under Uncertainties M.R.Soltanpour, M.M.Fateh

More information

A Sliding Mode Controller Using Neural Networks for Robot Manipulator

A Sliding Mode Controller Using Neural Networks for Robot Manipulator ESANN'4 proceedings - European Symposium on Artificial Neural Networks Bruges (Belgium), 8-3 April 4, d-side publi., ISBN -9337-4-8, pp. 93-98 A Sliding Mode Controller Using Neural Networks for Robot

More information

Parametric Models in Survival Analysis

Parametric Models in Survival Analysis arametric Models in Survival Analysis Survival analysis in biostatistical applications involves the analysis of times to events (see Survival Analysis, Overview); for conciseness we refer to these times

More information

lity density function of MDOF structural systems under non-normal delta-correlated inputs

lity density function of MDOF structural systems under non-normal delta-correlated inputs ELSEVIER Comput. Methods Appl. Mech. Engrg. 168 (1999) 121-133 Computer methods in applied mechanics aad engineerlag Dipartimento Probab di C lity density function of MDOF structural systems under non-normal

More information

PERGAMON Annual Reviews in Control 26 (2002)

PERGAMON Annual Reviews in Control 26 (2002) Annual Reviews in Control PERGAMON Annual Reviews in Control 26 (2002) 139-149 www.elsevier.com/locate/arcontrol ROBUST VEHICLE STEERING CONTROL DESIGN BASED ON THE DISTURBANCE OBSERVER Tilman Biinte *

More information

Energy 49 (2013) 279e288. Contents lists available at SciVerse ScienceDirect. Energy. journal homepage:

Energy 49 (2013) 279e288. Contents lists available at SciVerse ScienceDirect. Energy. journal homepage: Energy 49 (203) 279e288 Contents lists available at SciVerse ScienceDirect Energy journal homepage: www.elsevier.com/locate/energy Using multi-output feedforward neural network with empirical mode decomposition

More information